void rotate_fd(FrequentDirections* self){
double* S = (double*) malloc(sizeof(double) * self->m);
double* U = (double*) malloc(sizeof(double) * self->m * self->m);
double* Vt = (double*) malloc(sizeof(double) * self->m * self->dimension);
int info = LAPACKE_dgesdd(LAPACK_ROW_MAJOR, 'S', self->m, self->dimension, self->sketch, self->dimension, S, U, self->m, Vt, self->dimension);
// compute S*Vt
for(int i=0; i < self->ell; i++){
S[i] = sqrt( pow(S[i],2) - pow(S[self->ell - 1],2) );
for(int j=0; j < self->dimension; j++)
self->sketch[i * self->dimension + j] = Vt[i * self->dimension + j] * S[i] ;
}
memset(&self->sketch[self->ell * self->dimension], 0, self->ell * self->dimension * sizeof(double));
self->nextRow = self->ell;
free(S); free(U); free(Vt);
}
static void bench_gesdd(int size, double *A, double *U, double *VT, double *S)
{
int i, iter = 1;
double start, stop;
double gflops, peak;
if ((double) size * (double) size * (double) size <= 1.e12) iter = 2;
if ((double) size * (double) size * (double) size <= 1.e10) iter = 3;
if ((double) size * (double) size * (double) size <= 1.e8) iter = 5;
peak = 0.;
for (i = 0; i < iter; i++) {
start = gettime();
LAPACKE_dgesdd(LAPACK_COL_MAJOR, 'A', size, size, A, size, S, U, size, VT, size);
stop = gettime();
gflops = getgflops(size, stop - start);
if (peak < gflops) peak = gflops;
}
printf("%4d, %10.3f\n", size, peak);
fflush(stdout);
return;
}
